Capacitor is used as a battery for storing or discharging electricity, or being utilized for its direct current blocking characteristics, and has a structure wherein a dielectric material is inserted between the two closely placed electrodes which are insulated from each other.
When a direct current is applied to the capacitor, the current starts to flow while the charges are being accumulated in each electrode, but the current stops to flow when the accumulation of the charges are completed. However, if the direct current is applied again after changing the electrodes, the current starts to flow instantaneously. Using such characteristics, the capacitor is used for blocking direct currents but passing the alternate currents, and also it is used for storing electricity.
Such capacitors are classified according to the types of dielectric materials used therein such as air, vacuum, gas, liquid, mica, ceramics, paper, plastic film, electrolyte, and the like.
As for electrolytic capacitors, there are aluminum electrolytic capacitors and tantalum electrolytic capacitors, and electrolytic capacitors generally means aluminum electrolytic capacitors. Electrolytic capacitor uses thin oxide film as a dielectric material and aluminum is used as an electrode material. Since very thin dielectric material can be made, relatively large capacitance can be obtained compared with the volume of the capacitor.
Meanwhile, recently researches on multi-layered ceramic capacitor (MLCC) which is made of alternately stacked ceramic layer and metal (nickel) layer are being actively conducted. A multi-layered ceramic capacitor is made by alternately stacking 200 to 1000 of ceramics layers and metal layers within 0.3 mm height which is a typical thickness of a hair.
A multi-layered ceramic capacitor can store electricity by stacking a plurality of ceramics layers and nickel layers using the principle that nickel conducts electricity since it is a metal, but ceramics cannot conduct electricity.
Multi-layered ceramic capacitors are essential components for the electronic products such as mobile phones, smart phones, LCD TVs, computers, and the like, each requiring several hundreds of MLCCs therein. Miniaturization trends in electronic apparatuses demand MLCCs of smaller in size but having larger capacitance, which require high level technologies.
However, the thickness of such MLCCs become thicker when stacking a plurality of layers, and, moreover, since expensive process equipments are used in continuous stacking of multiple metal layers and insulation layers, thereby increasing manufacturing cost.